In recent years, since it has become clear (Japanese Patent Application Laid-Open No. HEI 4-300828) that diglycerides have obesity preventive action or weight gain inhibitory action, there has been an attempt to add them to various foods. In addition, it is reported (JP 2848849) that use of a glyceride mixture containing a high concentration of diglycerides as an oil phase makes it possible to provide an edible oil-in-water emulsified composition which has rich fat feeling and good taste even at a reduced fat content.
To an acid oil-in-water emulsified composition such as mayonnaise or emulsified dressing containing mayonnaise, a yolk is usually added in an amount of 0.5 to 20 wt. % (which will hereinafter be called “%” simply) as an emulsifying agent or for the purpose of taste improvement.
The present inventors therefore prepared an acid oil-in-water emulsified composition by emulsifying, with a yolk, an oil phase containing diglycerides in a high concentration.
It was however revealed that the mayonnaise prepared as described above had a markedly lowered commodity value because cracks appeared during storage, water separated from the cracks oozed out, it had a gloss-free and texture-roughened appearance and it exhibited gel-like physical properties. Such phenomena do not occur in a commercially available mayonnaise containing triglycerides as an oil phase and they have been serious hindrances to the incorporation of diglycerides in a high concentration (at least about 30%). When the amount of a yolk was decreased with a view to overcoming such problems, cracks did not appear but stable emulsification was not attained and the resulting mayonnaise became poor in a yolk taste.
An object of the present invention is therefore to provide an acid oil-in-water emulsified composition which has, even if it contains diglycerides in a high concentration and the amount of a yolk is not reduced, excellent storage stability, for example, is free from cracks during storage, and at the same time, has gloss, appearance of fine texture, excellent taste and cream-like physical properties.